[…] with CyberTracker (mostly bird and flowering plant observations). However there has been at least one time I could not even remember for sure where the photo was taken, nor could I determine from my observation […]

no – I hadn’t considered rat tracks. Do you think they might be plausible?

I wouldn’t imagine a rat doing the big jumps, and also wouldn’t tend to think of a rat down on the beach. Of course I also don’t tend to think of squirrels spending much time on the beach either. I know rats are around here, but I’ve had very little interaction with them or their tracks/sign that I know of.